Extraction device

ABSTRACT

In an extraction device ( 1 ) for extracting objects ( 2 ), in particular clots, foreign bodies, etc., from cavities ( 3 ) in a human or animal body, with first and second compressible and expandable collecting baskets ( 10, 20, 102, 110 ) between which the object ( 2 ) can be captured, said collecting baskets being mutually displaceable and being able to be drawn one into the other, at least one collecting basket ( 10 ) is umbrella-like in the expanded state and is designed with flexible wire-like adjustment elements for deliberately changing the shape and/or position of the collecting basket so that the object can be captured in the latter and can be drawn into the other collecting basket ( 20 ).

The invention relates to an extraction device for extracting objects, inparticular clots, foreign bodies, etc., from cavities in a human oranimal body, with first and second compressible and expandablecollecting baskets between which the object can be captured, whichcollecting baskets are mutually displaceable and can be drawn one intothe other.

Even in the era of prophylactic anticoagulation, acute pulmonaryembolism represents a frequent and often life-threatening event. Incases of massive pulmonary embolism, standard treatment consists ofmedicinal thrombolysis with streptokinase, urokinase or tissueplasminogen activator. The objective of this is the recanalization ofthe affected vessel. After these standard treatments have been applied,monitoring by imaging processes such as echocardiography, angiography orcomputed tomography, shows only slight recanalization afterthrombolysis. Despite high-dose thrombolysis, therefore, some patientsdie of right heart failure.

Alternatively, if thrombolysis is contraindicated, for example in casesof intracranial injury or after operations, or if thrombolsysis hasfailed, the embolus material can be removed surgically. The interventionusing a heart-lung machine places a considerable physical burden on thepatient and is associated with a high mortality rate.

Therefore, various devices have been developed to make clearance andrecanalization of the vessels easier.

In 1964, Greenfield developed a mechanical instrument withendoscope-like control which extracts pulmonary emboli non-surgicallyvia a venous puncture. Because of its complicated handling, this suctioncatheter did not gain widespread acceptance. In 1991, Gunther andSchmitz-Rode developed a high-speed catheter system for fragmentation ofpulmonary emboli which, because of its technical complexity and theinsufficient pulmonary control of the catheter, also failed to gainwidespread acceptance. A modified pigtail catheter developed by Guntherand Schmitz-Rode in 1995 is moved in rotation in the embolic occlusionand in this way effects coarse fragmentation of the embolus material.However, only the soft and fresh embolus material can be removed in thisway. The modified pigtail catheter fails in cases where there are moresolid, organized emboli. In the case of pulmonary arteries filledcentrally to peripherally with embolus material, there is littleprospect of successful recanalization by fragmentation, since thefragments cannot float off toward the periphery.

These disadvantages do not arise in US 2002/0095161 A1. In this devicefor extracting stones from the ureter, for example, these stones arecaptured in a basket having a large opening which covers over half ofthe surface of the basket and through which stones and stone fragmentscan pass into the interior of the basket. In addition, the basket hasrelatively narrow openings which are.suitable for holding back thestones and stone fragments. A disadvantage of this has proven to bethat, despite the possibility of rotating the basket, the capturingoperation is relatively awkward and the stone to be captured does notpass into the basket without any problems.

A similar problem arises in the extraction device according to U.S. Pat.No. 5,779,716 in which a sack-like collecting basket is provided with awire at its proximal end, which wire keeps the proximal opening of thesack-like collecting basket open in order to assist in the capturingoperation.

The prior art also includes extraction devices with coiled wires betweenwhich a stone or other foreign body can be captured. An example of thisis set out in WO 99/47054. There is a risk here of the stone escapingfrom the loops while being drawn back in the recovery operation. Thisapplies also to the extraction device disclosed in WO 01/05311 A1 and tothe extraction device disclosed in US 2002/0026203 A1.

Gripper-like means which take hold of the stone to be recovered andsecure it during the recovery operation are likewise known in the priorart, for example from WO 00/54672 A1.

To remove clots from the vessel system, U.S. Pat. No. 5,419,774 Adiscloses an extraction device whose distal end is provided with achamber into which the clot is drawn by suction. Situated in the chamberthere is a separating device which separates that part of the clot thatis situated in the chamber. A pressurized fluid is delivered in order tocarry off the clot and the blood collecting with the latter. Thestructure of the device, however, is relatively complicated since, onthe one hand, a means for applying a partial vacuum has to be providedand, on the other hand, a means for delivering a pressurized fluid.Moreover, a means has to be provided for separating the clot. Thesedisadvantages also apply to the catheter for working on and removingsoft and hard substances for use in invasive microsurgery and vesseltreatment according to DE 197 34 890 C1. The area of application of thelatter is the removal of tissue or gallstones, for example.

For removal of clots, it is also known in the prior art, from U.S.2002/0026211 A1, to provide a device and a method for filtering ofemboli or removal of clots from a vessel, in which the device has avascular filter for trapping the emboli and optionally a thrombectomyelement for removal of the clot. The vascular filter contains a supportring with one or more hinge areas which are secured near a distal end ofa guide wire, and a blood-permeable pouch which is secured on thesupport ring. The support ring forms the opening of the blood-permeablepouch and holds it open. It is possible to provide two pouches onebehind the other, their openings pointing in the same direction, namelyin the proximral direction. The first vascular filter captures the clot,the second one the remaining emboli. Both vascular filters are retractedinto a tube or catheter together with the clot or the emboli. Thisdevice proves disadvantageous on account of the support rings inconjunction with the blood-permeable pouch since the hinges provided inthe support rings make it expensive to produce. In addition, because ofthe use of a support ring, the risk of damaging the vessel from whichthe clot or emboli are to be removed is very high, since this supportring is rigid and immovable compared to the vessel and may scrapeagainst the inside wall of the vessel.

A further device for the removal of clots is known from U.S. Pat. No.5,011,488 A. Here, a vascular catheter system comprises an outerflexible tube, an inner flexible tube disposed in the lumen of the outerflexible tube, and an expandable body mounted at the distal end of athird flexible tube itself disposed in the lumen of the inner flexibletube. The inner tube includes an expandable tip which can open to adoptsubstantially the cross section of a blood vessel. The expandable bodyis positioned in the clot region and expanded. The clot material to beremoved is then situated between the two expanded parts, the expandedtip being an inflatable body which bears against the inside wall of thevessel and, when drawn back into the tube, scrapes the clot material offfrom the inside wall of the vessel and carries it toward the expandedbody. The inflatable body or balloon fits into the expanded open bodyand has a truncated cone shape corresponding to the latter. The expandedbody has a plurality of spring elements which, after being pushed out ofthe tube, lead to opening of the expandable tip. Because of thetruncated cone shape, the expanded body is pushed together again whendrawn back into the tube. The same happens to the inflatable body orballoon then lying on the inside. This device proves disadvantageoussince, when the two bodies are drawn back, the clot material locatedbetween them can escape again, especially when the inflatable body iscompressed, i.e. it is not held securely between the inflatable body andthe expandable open truncated cone shaped body.

WO 00/51505 A1 discloses an extraction device with only a distal portionwhich can be widened like a balloon and has intertwined wires covered bya woven fabric. To clear a vessel, the widened end scrapes along thevessel wall and the woven fabric prevents penetration of scraped-offforeign bodies into the device or into the widened portion.

DE 692 28 326 T2 discloses an extraction device in which a flexible looppart is covered with a net and secured at its distal end and proximalend on a tensioning wire. By moving the loop part along the tensioningwire, it is possible for the net to assume an open form and a closedform. In this way, a foreign body can be captured in the loop partcovered with mesh.

WO 00/53120 A1 discloses an extraction device in which two collectingbaskets are provided with the openings of the collecting basketsdirected toward one another. The distal collecting basket is secured ona rod and is arranged inside the other collecting basket so that it canbe drawn inside the latter. The distal collecting basket has a distalcontracted end, whereas the proximal collecting basket has a proximalcontracted end.

The object of the present invention is to avoid the aforementioneddisadvantages of the prior art and create an extraction device forextracting objects, in particular clots, foreign bodies, etc., fromcavities in a human or animal body, in which device the object issecurely covered so that it can be safely recovered and then removedfrom the cavity of the human or animal body. In particular, the aim isto permit effective and non-surgical recanalization in the case ofpartially organized emboli and in cases of extensive embolization of thepulmonary circulation.

The object is achieved with an extraction device in accordance with thepreamble of claim 1 in which at least one collecting basket isumbrella-like in the expanded state and is designed with flexiblewire-like adjustment elements for deliberately changing the shape and/orposition of the collecting basket so that the object can be captured inthe latter and can be drawn into the other collecting basket. For anextraction device in accordance with the preamble of claim 5, the objectis also achieved by the fact that at least one wire-like flexibleadjustment element is secured on the distal and/or proximal end in sucha way that the at least one collecting basket can be deliberatelycontrolled and changed in shape. Developments of the invention aredefined in the dependent claims.

Thus, an extraction device for extracting objects, in particular clots,foreign bodies, etc., from cavities in a human or animal body is createdwhich makes it possible in particular for emboli, in particular inpulmonary arteries, to be captured, covered and compressed so that theycan be safely recovered from the circulatory system by way of the rightheart and removed via the percutaneous venous access either by thefemoral route or by the jugular route. Using at least one umbrella-likecollecting basket which can be drawn into the other collecting basketmeans that it is possible for clot particles to be squeezed in thecollecting baskets so that the large percentage of fluid present in theclot can escape, and thus only small clot particles are carried off withthis fluid into the blood circulation system, so that this no longerposes a life-threatening risk. The larger clot particles, by contrast,are drawn through a channel element from the human or animal body sothat they too no longer represent a threat to life. The extractiondevice can therefore be used in particular as a thrombectomy system,making it possible in particular to avoid massive pulmonary embolism.Vascular deposits can be taken up and removed, this being possible inparticular also for the vessels leading in the direction of the brain.Another area of application is the removal of foreign bodies, which alsoincludes for example the removal of kidney stones, gallstones and otherbodies forming in the organism. Moreover, “real” foreign bodies can beremoved, for example from the lung system, from the gastrointestinalsystem and generally from all the cavities of a human or animal body.The extraction device is thus designed not only for use in all vesselregions, for example in miniaturized form for thrombectomy inhemodialysis shunts, in minimally invasive surgery and robotic surgicalinterventions, but generally for removal of all kinds of foreign bodiesor bodies from cavities of a human or animal body, for example also bylaparoscopy.

By providing the at least one collecting basket with an umbrella shapehaving flexible wire-like adjustment elements, it is possible to obtainany desired adjustment in size and thus any change in the collectingrange. The umbrella-like collecting basket preferably opens toward theother collecting basket. In this way, the object, for example clot,foreign body, etc., can be captured between the two collecting basketsoriented with their openings toward one another and thus collected.“Escape” of the object is no longer possible. Alternatively, theumbrella-like collecting basket can open in the direction pointing awayfrom the other collecting basket. This possibility proves advantageousif the one collecting basket cannot be guided past the object to berecovered and take hold of said object from the other side. Therefore,both collecting bodies are arranged on the same side, namely on theproximal side, of the object, and the umbrella-like collecting basketengages the object from this proximal side. However, the latter is thenlikewise drawn into the other collecting basket in order to recover itand if possible compress it.

Both collecting baskets are preferably provided with at least oneadjustment element for adjusting the shape and/or position of thecollecting baskets. The at least one adjustment element is used to movethe collecting basket forward and backward in the cavity from which theobject, e.g. clot, foreign body, etc., is to be removed and foradjusting the shape and size of the collecting basket so as to permiteffective adaptation to the object and to the latter's position. The atleast one adjustment element preferably has one or more thin wires.These wires permit particularly good and exact change of shape of thecollecting basket. In at least one collecting basket, actuation of theadjustment elements can lead to widening of the collecting basket. Thisproves especially advantageous in the collecting basket into which theother collecting basket is to be drawn. The other umbrella-likecollecting basket is advantageously also provided with adjustmentelements in order to position it around the clot, foreign body, etc., insuch a way that the latter can be safely captured. This cruciallydistinguishes the collecting baskets according to the invention fromthose disclosed in US 2002/0095161 A1, since the latter discloses only alarge distal collecting basket without adjustment elements asadvantageous. With likewise preferred provision of a guide cannulasecured at the distal end of the collecting basket or of the firstcollecting basket, the width of opening in particular of this firstcollecting basket can be altered if proximal adjustment elements areprovided. In this case, the collecting basket can be kept at the optimumlocation by the guide cannula and can be opened as far as is necessaryby the adjustment elements. In the case of a channel element which islikewise preferably provided and through which the collecting bodies canbe conveyed to the site where the object, e.g. clot, foreign body, etc.,lies in the hollow cavity, the collecting basket can be drawn backtogether with the guide cannula and the adjustment elements, withcompression of the collecting basket or collecting baskets taking place.

The at least one adjustment element is preferably arranged on theoutside and/or inside of the at least one collecting basket. The atleast one adjustment element is particularly preferably integrated atleast partially into the circumferential surface of the collectingbasket and/or laced into it. This proves especially advantageous in thesecond collecting basket which receives the first collecting basket, soas to be able to bring it into an optimal shape in a deliberate andreproducible manner. The proximal end of the collecting basket ispreferably secured in a tubular element, in particular a catheter, andthe at least one adjustment element is routed through the tubularelement. By applying a force in the distal or proximal direction, thecollecting basket can be adjusted in shape. The collecting basket ispreferably designed in such a way that it shortens in its longitudinaldirection when it is widened, and lengthens when its cross section isreduced. The at least one collecting basket can preferably be expandedto a diameter greater than the diameter of the cavity, in particularvessel, to be cleared, so as to permit partial widening of said vessel.This advantageous possibility of shortening of its length means that, atthe same time as the vessel widens and upon positioning in front of anobject to be captured, this object can automatically spring into thecollecting basket. In the stents known from the prior art, suchshortening is absolutely not wanted for bringing foreign bodies intothem in a particularly effective manner. In the context of the presentinvention, however, the change in cross section and the shortening ofthe length of the collecting basket prove especially advantageous forthe collecting procedure.

To strengthen the connection between tubular element and collectingbasket, a sleeve element can preferably be provided at the proximal endof the collecting basket. This sleeve element, however, isadvantageously applied in such a way that adjustment in particular ofthe shape of the collecting basket is easily possible via the adjustmentelements.

The at least one adjustment element preferably protrudes beyond theoutstretched length of the at least one collecting basket and ispreferably arranged to be actuated from the proximal end. To actuate theadjustment element or elements, a handgrip is preferably provided, inwhich case the adjustment elements of all the collecting baskets canpreferably be actuated via one handgrip. The handgrip for this purposepreferably has different actuating elements to which the individualadjustment elements can be secured.

The adjustment element or elements are preferably secured on thecollecting basket in a branched-out configuration and are broughttogether in groups proximally. This proves especially advantageous onthe umbrella-like collecting basket so that the latter can be guidedespecially effectively around the object, for example clot, foreignbody, etc., and can be drawn back smoothly to the channel element orsecond collecting basket. The at least one adjustment element ispreferably made in one piece with the collecting basket. In this way,there is no risk of the adjustment elements coming loose from thecollecting basket. Moreover, the actuating force can continue optimallythrough the circumferential surface of the collecting basket, so thatthe actuation of the at least one adjustment element as soon as possibleprovides the desired effect of adjustment of the collecting basket.

The distance between the distal end of the collecting basket and the atleast one proximal point of attachment or point of emergence of the atleast one adjustment element remains constant for different designs ofthe collecting basket. This proves advantageous upon introduction intothe channel element because there is no risk of losing the capturedforeign body, clot, etc. Staggering of the movement of insertion intothe element can also be avoided by this means.

Reducing elements are preferably provided transversely with respect tothe longitudinal extent of the at least one collecting basket, inparticular in the area of the proximal and/or distal ends of thecollecting basket and/or in the area of the at least one proximal pointof attachment or point of emergence of the at least one adjustmentelement. The reducing elements are particularly preferably nooses. Inthis way, before insertion into the channel element or a catheter, theat least one collecting basket can be closed so that the object istrapped completely in the collecting basket and cannot accidentallyescape back into the cavity, in particular into a blood vessel. Thisproves especially advantageous for the umbrella-like collecting basket.

At least one collecting basket is preferably composed of a braidedfabric and/or woven fabric and/or scrim, in particular a wire braidand/or woven wire fabric and/or wire scrim. The at least one adjustmentelement is particularly preferably made of part of the braided fabric,woven fabric or scrim. When a collecting basket made of such a braidedfabric, woven fabric or scrim is provided, the mesh size can be used todetermine the size of the particles which, after compression of thecollecting basket, are introduced into for example the channel elementor a catheter and back into the blood stream or generally the cavity ofthe human or animal body. Squeezing or pressing out of, in particular aclot or embolus, is thus possible in a particularly effective manner.Alternatively, at least one collecting basket can be made up of a tubewhich is slotted at least along part of its length. In this respect,reference is made in particular to DE 100 00 137 A1. The elements shownin particular in FIG. 1 of the latter document can advantageously alsobe used here as collecting bodies. It proves especially advantageous ifthe cut or cuts in the slotted tube are made in such a way as to affordthe maximum ratio of shortening and widening upon expansion of thecollecting basket in particular secured at the proximal end. It isparticularly preferable for the cut(s) in the slotted tube to be madelong by comparison with the longitudinal extent of the collectingbasket. In this way, it is possible to achieve especially good wideningand shortening during expansion of the collecting basket.

A guide wire or inner mandrel is preferably provided along which the atleast one collecting basket or the two collecting baskets can moveand/or can be introduced into the cavity. In this way, it is possible toprovide an optimal orientation with respect to the object to be captured(clot, foreign body, etc.), particularly upon withdrawal into thechannel element or a catheter.

At least the second collecting basket preferably has a self-openingpartial area and a self-closing partial area, which self-closing partialarea can be opened deliberately by at least one adjustment element. Inthis way, the object captured is retained particularly securely andeffectively.

The extraction device can preferably also be used in conjunction with anendoscope with or without the provision of the channel element. In thisway, the capturing and extracting procedure can be monitoredparticularly clearly from outside, since it is possible not just toadvance a viewing optic, but also a light source, to the operating site.

Partial areas of the at least one collecting basket preferably are madeof material with differing diameter. It is particularly preferable thatan expandable partial area of the at least one collecting basket is madeof a material with a thinner cross section or preferably has a braidedfabric, scrim or woven fabric with filaments of different diameterand/or cross section. In this way, a partial area of the collectingbasket can be made particularly easy to expand, whereas the partial areanot to be expanded, which is secured in particular on the tubularelement or catheter, can be made of material with a thicker crosssection or uniform cross section. This provides the advantageouspossibility of designing the collecting basket all across itscircumferential surface in such a way that certain areas can beparticularly easily expanded so as to permit the best possiblecollecting and extracting procedure. The material of the at least onecollecting basket is particularly preferably treated chemically and/ormechanically in at least a partial area, in particular etched,electrolytically polished, microground or otherwise treated. Inaddition, or alternatively, a partial area can by this means be providedwith expansion and compression properties different than those of theremaining areas of the collecting basket.

The at least one collecting basket is preferably made of a biocompatiblematerial, in particular a metal or a metal alloy, in particular astainless steel or nitinol. Partial areas of the at least one collectingbasket can also be made of different materials, in particular ones withdifferent mechanical properties. It is thus possible to providefilaments not just of different diameter, but also of differentelasticity, flexibility and/or mechanical loading capacity.

The guide cannula and/or the tubular element(s) are preferably made of aflexible material, in particular a metal, a metal alloy, a plastic oranother flexible material or a combination of materials, in particularnitinol. Depending on the site of use and type of use, it proves helpfulif the guide cannula and/or the tubular element(s) can simulate thebends of a blood vessel or of another vessel or cavity into which theyare introduced. Depending on the location from which the extractiondevice is introduced into the patient's body, a greater or lesser numberof bends have to be simulated. Therefore, the channel element is alsoadvantageously made of a stable and at least partially flexiblematerial, in particular of a plastic, metal, a metal alloy, inparticular nitinol, in particular a thin-walled nitinol tube. However,it is preferably configured in such a way that there is no risk ofinjury to the vessel or other cavity into which the channel element isintroduced. The adjustment elements can on the one hand be part of thebraided fabric, woven fabric or scrim or also part of the slotted tubeof the collecting basket. The provision of a slotted tube in the form ofa collecting basket proves advantageous especially in terms of thereproducibility of the shape since, with laser cutting of the tubes,machine automation leads to a considerable reduction in productioncosts. Therefore, the adjustment elements are advantageously made of thesame material as the at least one collecting basket or the collectingbaskets. The tubular element too can therefore preferably be designed inone piece with the second collecting basket and be provided at leastpartially with a cut permitting expansion and compression.

The invention is explained in greater detail below on the basis ofillustrative embodiments and with reference to the drawings, in which:

FIG. 1 shows a plan view of a first embodiment of an extraction deviceaccording to the invention,

FIG. 2 shows a plan view of an alternative embodiment of a secondcollecting basket according to the invention for an extraction deviceaccording to FIG. 1,

FIGS. 3 a) through c) show sketches of three end areas of collectingbaskets designed according to the invention,

FIG. 4 shows a plan view of a first collecting basket designed accordingto the invention with guide sleeve, guide wire, adjustment elements,catheter and channel element,

FIG. 5 shows a plan view of a second embodiment of the first collectingbasket, with the object to be captured,

FIG. 6 shows a plan view of a third embodiment of a first collectingbasket according to the invention,

FIG. 7 shows a plan view of a fourth embodiment of a first collectingbasket according to the invention,

FIG. 8 shows a plan view of a fifth embodiment of a first collectingbasket designed according to the invention,

FIG. 9 shows a plan view of a sixth embodiment of a collecting basketdesigned according to the invention and with reducing elements,

FIG. 10 shows a plan view of a seventh embodiment of a first collectingbasket,

FIG. 11 shows a plan view of an alternative embodiment of an extractiondevice according to the invention,

FIG. 12 shows a plan view of a further alternative embodiment of a firstcollecting basket according to the invention,

FIG. 13 shows a plan view of a second collecting basket with adjustmentelements, in the compressed state,

FIG. 14 through FIG. 19 show individual steps in the collectingprocedure using the second collecting basket according to the presentinvention,

FIGS. 20 a) and b) show a sketch of a further embodiment of a collectingbasket according to the invention, cut from a slotted tube, in thecompressed state (a) and expanded state (b),

FIG. 21 shows a perspective view of an alternative embodiment of anextraction device according to the invention,

FIG. 22 shows a front view of the extraction device according to FIG.21,

FIG. 23 and FIG. 24 show perspective side views of the extraction deviceaccording to FIG. 21 in a position of maximum projection from thechannel element and in a position in which it has been partially drawninto said channel element,

FIGS. 25 a) through e) show individual steps in the process ofrecovering pulmonary emboli using an extraction device according to FIG.21 and bringing them into a channel element,

FIG. 26 shows a further embodiment of the extraction device according toFIG. 21 in which an eccentric guide wire is provided as a single-strutcollecting basket,

FIG. 27 shows a further embodiment of an extraction device according tothe invention with first and second collecting baskets,

FIG. 28 shows a further embodiment of an extraction device according tothe invention with a coating applied to the mesh-like structure of thecollecting basket,

FIG. 29 shows a perspective view of the extraction device according toFIG. 28 provided with a separating means in the form of a wire withattached ball, and

FIG. 30 shows details of different embodiment variants of wire ends of aseparating means.

FIG. 1 shows a first embodiment of an extraction device 1 according tothe invention with a first collecting basket 10 and a second collectingbasket 20.

Both collecting baskets are guided along a guide wire 30. They haveadjustment elements 11, 21. The adjustment elements 11 of the firstcollecting basket are, like the guide wire 30, routed through the secondcollecting basket 20. The adjustment elements 11 and the guide wire arelikewise routed through a catheter 40. All or some of the adjustmentelements 11 can be guided displaceably or movably within said catheter.

The adjustment elements 21 of the second collecting basket arepreferably routed outside the catheter in order to permit a betterrelative movement of the first and second collecting baskets and aboveall to permit adjustment of the second collecting basket. The secondcollecting basket is secured on the catheter 40, as can be seen fromFIG. 2.

The first and second collecting baskets and the catheter 40 can be drawninto a channel element 50. The channel element 50 can itself be acatheter. It is pushed into a cavity of a human or animal body, inparticular into a vessel, in order to bring the collecting baskets to anobject 2 to be removed from the cavity 3. The object can, for example,be a clot, a foreign body, an embolus or another object which is lyingin a vessel, in the pulmonary system, in the gastrointestinal system,the kidneys, the gallbladder or another part of the body or a cavity ofa human or animal body and which is to be removed from there. Tomaintain the path through the body or cavities, the guide wire 30 isprovided. This can have an atraumatic tip in order to avoid injury tothe cavity, in particular the blood vessel.

The first collecting basket 10 has an umbrella-like design and comprisesa distal closed end 12 and a proximal open end 13. Upon introductioninto the channel element and in particular into the catheter, thecollecting basket composed of a braided fabric is strongly compressed,whereas, after it has been pushed out from the channel element and thecatheter, it expands so that its proximal end is able to receive theobject that is to be removed.

By means of the adjustment elements 11, the first collecting basket canbe positioned so that it is oriented optimally over the, object andpushes the latter in the direction of the second collecting basket afterit has received said object. FIG. 1 shows the position where the firstcollecting basket has not yet received the object.

The second collecting basket 20 is shown in FIG. 1 as a. tubularelongate element. However, it can also have any other desired shapes, inparticular the one shown in FIG. 2. In the latter, the proximal end 23is secured in a sleeve element 24 and a tubular element 25. The distalend 22 of the second collecting basket is open, as in the embodimentaccording to FIG. 1. In the embodiment according to FIG. 2, the secondcollecting basket thus acquires a tulip shape. It is then possible, inparticular by provision of adjustment elements, to ensure even betteropening of the distal end of the second collecting basket for receivingthe first collecting basket and the object to be recovered.

The second collecting basket is also made of a woven fabric. To permitbetter widening at least of the distal end 22 of the collecting basket20, this woven fabric can be composed of filaments of differentdiameter. For example, a first filament 26 has a diameter of 0.20 mm anda second filament 27 has a diameter of 0.15 mm. However, any otherdesired diameters can also be chosen. These filaments of differentdiameter are intertwined, in particular alternately intertwined. In apartial area x, indicated in FIG. 2, it is possible simply to use athinner filament and, in a second partial area, to use a thickerfilament so that the first area can be widened better than the secondarea. This also makes it easier to receive objects in the distal area ofthe second collecting basket. It is also possible to use differentfilament diameter combinations in different areas.

FIG. 3 shows various possible ways in which the collecting baskets canbe finished at the distal end and/or the proximal end. FIG. 3 shows onlythree different possibilities; there are, however, a great many others.Possibility a) indicates an interlacing of respectively contiguousfilaments, as is customary in basket weaving. Variant b) indicates aninterlacing with a smaller overhang at the edges, as is also customaryin basket weaving. In variant c), eyelets are formed, as is advantageousin particular for applying adjustment elements to the first and secondcollecting baskets. Any desired combination of the three variants or ofothers can also be formed. FIG. 3 also indicates the different filamentthicknesses.

A detail of the first collecting basket 10 is shown in FIG. 4. In thisembodiment, the first collecting basket is secured on a guide cannula 14via its distal end 12. The guide wire 30 is routed through the guidecannula. The adjustment elements 11 of the first collecting basketextend outside the guide cannula. The guide cannula, adjustment elementsand guide wire are routed through the catheter 40. The latter in turn isarranged inside the channel element 50. In this embodiment, the secondcollecting basket is not present. The object can also be recoveredwithout the second collecting basket.

In contrast to the embodiments of the first collecting basket accordingto FIG. 1 and FIG. 4, in the embodiment of the first collecting basketaccording to FIG. 5 the adjustment elements 11 are not securedseparately on the collecting basket, but instead are made in one piecewith the latter. Parts of the braided fabric of the first collectingbasket are thus guided out and branched at the proximal end, withseveral filaments or wires of the braided fabric in each case beingtwisted together. This twisting together results in a plurality ofadjustment element parts 15. These in turn are brought together in sucha way that only two adjustment element parts 16 are routed to thecatheter. The object 2 recovered in the first collecting basket 10 islocated between the adjustment element parts 15.

In the embodiment according to FIG. 6, the adjustment element parts 15are omitted and the individual ends of the braided fabric of the firstcollecting basket are brought together directly to form two adjustmentelement parts 16.

FIG. 7 shows an embodiment similar to FIG. 6, but in FIG. 7 some of thefilaments 17 form loops at the proximal end and are routed back to thedistal end, and only a few filaments form the adjustment element part16.

In the embodiment according to FIG. 8, the filaments, in contrast to theother embodiments of the above-described first collecting baskets 10,are divided into two parts at an area distant from the proximal end ofthe collecting basket and these two parts are then guided together toform the two adjustment element parts 16.

In each embodiment of the first collecting baskets 10, when these aredrawn into the catheter and/or into the channel element, the distance alof the distal end 12 from the proximal point of attachment 18 or pointof emergence 19 remains substantially constant in order to permit simpleintroduction into the channel element or catheter. The point ofattachment 18 here is intended to signify the point where the adjustmentelements are attached to the first collecting basket, and the point ofemergence is intended to signify the point where the adjustment elementsformed in one piece with the collecting basket emerge from the braidedfabric thereof.

FIG. 9 shows a further embodiment of a first collecting basket 10designed according to the invention. In this embodiment, the filaments17 at the proximal end are essentially interlaced in such a way that astraight finish is obtained. The ends of the filaments are guidedtogether into the two adjustment element parts 16 in the area of thepoints of emergence 19 from the braided fabric. In this area, a reducingelement 60 in the form of a noose is also provided. The noose is guidedround the entire circumference of the distal end of the collectingbasket 10. The noose element can preferably be actuated from outside ofthe patient's body. In this way it is possible to reduce the diameter ofthe opening at the proximal end of the collecting basket. An objectrecovered in the collecting basket can thus be better secured in thelatter. At the distal end of the first collecting basket there is also areducing element 61 which is likewise present in the form of a noose andis provided for reducing the diameter or for tying off this end. FIG. 9also very clearly shows the formation of the distal end in respect ofthe interlacing of the individual filaments of the collecting basket.The distal end can thus be produced either by continuous intertwining orinterlacing of the individual filaments or by tying off with a reducingelement, as is indicated in FIG. 9. In FIG. 9, the adjustment elementparts 16 are configured as tubular elements, which in particular can bemade of plastic or metal.

FIG. 10 shows a further embodiment of a first collecting basket 10designed according to the invention, with two adjustment elements 11,the collecting basket being asymmetrical, namely longer at one side. Thelengthening piece 70 is made from the same braided fabric as the rest ofthe collecting basket. The lengthening piece 70 on one side ispreferably drawn under the object to be recovered in such a way that thelatter slides almost automatically into the opening 71 at the proximalend of the collecting basket. The lengthening piece 70 can be controlledusing the two adjustment elements 11 secured at its proximal end 72.Instead of the two adjustment elements, it is also possible to use justone. At the proximal end 72 there is also a hook-shaped element 75 whichcan advantageously be engaged for releasing the collecting basket andfor removing the collecting basket from the body of the patient. Thisembodiment of a collecting basket is especially suitable as a vena cavafilter.

FIG. 11 shows a further embodiment of an extraction device 1 which isdesigned according to the invention and in which the collecting basket10 is formed with its opening 73 directed away from the opening 28 ofthe second collecting basket 20. In this embodiment, the firstcollecting basket is once again secured on a guide cannula 74, but, incontrast to FIG. 1, via its proximal end 13. The distal end 12 is wideopen in the view according to FIG. 11, so that an object to be recoveredcan be received therein.

The guide cannula 74 is routed through the second collecting basket andinto the catheter 40 provided at the proximal end of the secondcollecting basket. With its proximal end 23, the second collectingbasket is secured on the catheter 40 so as to be able to change itsshape and position by way of the adjustment elements 21, that is to saybe able to expand and compress it. The adjustment elements 21 arepartially worked into the circumferential surface 29 of the secondcollecting basket or laced through the braided fabric of thecircumferential surface. This permits particularly easy actuation of thesecond collecting basket. As is also shown in FIG. 11, the adjustmentelements 21 of the second collecting basket are also preferably routedoutside the catheter to its proximal end in order to permit actuationfrom outside the operating site. A channel element, through which thecatheter 40, the guide cannula 74 and the adjustment elements 21 can berouted, is passed through the patient's skin and into the correspondingcavity to a point just before where the object to be collected lies.This, however, is not shown in FIG. 11.

The extraction procedure, or the capture of an object and its removalfrom the cavity, is performed by the channel element or a catheter,optionally with inner mandrel, being placed via a guide wire in thecorresponding cavity, in particular a vessel. The catheter is positionedat a point over the object to be captured, in particular a clot, as faras its periphery. Then, the first collecting basket 10 is initiallyreleased. Thereafter, this is also done with the second collectingbasket 20, but the latter is pushed out of the catheter before the clotand deployed. In this way, the clot is flanked on both sides by thecollecting baskets. In the case of the embodiment according to FIG. 11,however, both collecting baskets are released before the clot so thatthe latter is located not only in front of the second collecting basketbut also in front of the first collecting basket. After the collectingbaskets have been released, the clot is captured using the firstcollecting basket and the latter is drawn back into the secondcollecting basket 20 together with the clot. For further recovery of theclot, both collecting baskets, in the state with one drawn into theother, are then drawn back into the channel element. Here, contractionof both collecting baskets takes place and, in this way, the clot issqueezed. This is done advantageously in the pulmonary artery or venacava.

Another object, for example a foreign body or a body formed by theorganism itself, such as a kidney stone or gallstone, is carried off ina corresponding manner, except that, depending on the consistency, theforeign body is not subjected to squeezing. It is simply recovered fromthe cavity and withdrawn to outside of the patient's body.

The guide wire is provided to maintain the approach route. To permitbetter control of the first collecting basket, the guide cannula can beused on this, as is shown in FIGS. 4 and 7 and FIG. 11. As can be seenin particular from FIG. 11, the adjustment elements, preferably wires,are secured at the ends, here the distal end 22 of the second collectingbasket. In this way, it is possible to ensure that the second collectingbasket can be optimally opened for drawing-in of the first collectingbasket.

FIG. 12 shows a further embodiment variant for the first collectingbasket 10. In contrast to the embodiment according to FIG. 11, this oneis turned through 180°, in other words now points with its openingtoward the distal opening of the second collecting basket. The guidecannula is in this way again secured at the distal end of the firstcollecting basket. This embodiment variant permits particularlyeffective capture of emboli, since these are often more widely scatteredin a vessel, and this embodiment variant affords a comparatively widelyopening collecting basket. The collecting basket shown in FIG. 12 can beobtained from the collecting basket 10 shown in FIG. 11 by turning thisthrough 180°, e.g. also by pulling on adjustment elements which can besecured at the open end of the collecting basket.

In FIG. 13, the second collecting basket 20 is shown with its adjustmentelements 21 and a catheter 40. The second collecting basket is shownsubstantially compressed, and the adjustment elements which contributeto the expansion are shown particularly clearly. Since it is the distalarea x that is to be expanded for receiving the first collecting basketor the object to be recovered, the adjustment elements in this area areshown drawn out from the circumferential surface. In this way it canalso clearly be seen that they are secured at the distal end 22 of thesecond collecting basket or laced through at this end, so that anadjustment element in each case adopts a forward and backward direction.The adjustment elements are guided outward at the proximal end 41 of thecatheter. At this location, said adjustment elements can be actuated, inparticular by a handgrip (not shown).

FIGS. 14 through 19 show different steps in the capture of an object,for example a foreign body in a vessel, by the second collecting basket20. In FIG. 14, the elongate and unexpanded collecting basket is shownsimilarly to the one shown in FIG. 13. The distal end 22 of the secondcollecting basket is still substantially closed. By contrast, FIG. 15shows an already opened distal end 22 of the collecting basket 20. Theopening or expansion of the collecting basket in this distal area x iseffected by the adjustment elements 21. In the upper part of the drawingin FIG. 15, the collecting basket is shown pushed out of the channelelement 50 inside a vessel, and it has already been partially pushedover the object 2.

FIG. 16 shows the second collecting basket 20 now further expanded. Inthe topmost view, the collecting basket has been opened so wide that itbears completely on the inside wall 4 of the vessel. In the positionindicated below this, the collecting basket, upon further expansion,partially opens the vessel further out, so that the vessel diameter dipartially assumes a diameter d₂. By means of this widening of thevessel, the object 2 slides automatically into the opening 28 of thecollecting basket. FIG. 17 shows the object once it has sprung or slidinto the second collecting basket. Here, the collecting basket is shownstill opened out at one end.

FIG. 18 shows a further step in capturing and recovering the object 2,in which step the adjustment elements 21 are released again. In thisway, the tubular collecting basket draws together again in the distalarea x, beginning in the area of the opening 28. In this way, the object2 is prevented from sliding back out of the collecting basket. From theupper part of the drawing in FIG. 18 it will also be seen that, uponcontraction of the collecting basket, the latter disengages again fromthe inside wall 4 of the vessel.

In the last step, which is shown in FIG. 19, the adjustment elements 21are loosened so far that the woven fabric of the second collectingbasket draws together again like a sock in the distal area x, so thatthe opening 28 is almost closed again at the distal end 22 of thecollecting basket. The object 2 is received completely within thecollecting basket. As will be seen from the upper part of FIG. 19, thecollecting basket can now be drawn back out of the vessel or cavity, asis indicated by the arrow 80.

As can be seen in particular from FIGS. 15, 16 and 17, when thecollecting basket opens out it also shortens. The more the collectingbasket shortens, the more effective is its widening out and the betterit is able to capture an object. This effect can be obtained not onlywith a wire braid or generally any braid of the collecting basket, butalso by provision of a slotted tube 90, as can be seen from FIG. 20. Theupper part of FIG. 20 shows the compressed slotted tube with cuts 91,whereas the lower part of FIG. 20 shows the expanded tube provided withcuts 91. In the embodiment shown, the arrangement of the cuts 91 issimilar to the ribs of a skeleton, the individual cuts being arrangedsubstantially parallel to one another. However, any other desired shapeof cuts can also be chosen if it permits expansion and subsequentcompression of the tube for changing its cross section. By providingparticularly long cuts, a considerable change of cross section is madepossible. The embodiment variant of a slotted tube shown in FIG. 20 isespecially suitable for the second collecting basket. For the firstcollecting basket, a variant such as the one disclosed in DE 100 00 137can be used, in particular the variant shown there in FIG. 1.

The present extraction device can also be used in conjunction with anendoscope. Endoscopy involves the provision of light sources, an opticaldevice and a working channel. For use with an endoscope, the secondcollecting basket 20, for example, is clamped onto the first collectingbasket 10 from outside. This can be obtained through the self-clampingforce arising from the prestressing of the woven fabric or slotted tubeof the second collecting basket. Independently of the use together withan endoscope, this self-clamping force is otherwise used in particularfor holding the captured object. The first collecting basket 10 issubsequently introduced through the working channel. The secondcollecting basket 20 follows on from outside, owing to it being clampedto the first collecting basket. During the transport to the operatingsite, the second collecting basket clamped from outside holds secure. Atthe operating site, both collecting baskets are then opened. Ifappropriate, a channel element can be pushed over both collectingbaskets and introduced into the working channel. In this mode of use,endoscopes with a diameter of 3 mm are especially suitable. Depending onthe application, however, it is also possible to use larger endoscopes,for example endoscopes with a diameter of 10-15 mm. The way in which theobject to be recovered is captured corresponds to the procedure alreadydescribed above.

FIG. 27 shows a combination of some of the above-described embodimentsof first collecting basket and second collecting basket. The secondcollecting basket 20 opens automatically in the distal area x. This partadapts and bears against the wall of the vessel or cavity. The proximalpartial area y remains compressed or folded, but can be actively openedby pulling on the adjustment elements 21. After release of theadjustment elements 21, this proximal partial area is compressed againand, because of its imparted shape and shape-retaining force, securelyholds the clot, emboli, etc.

FIGS. 21 and 22 show a further embodiment variant of the collectingbasket 20. This is similar to the one shown in FIG. 2. The adjustmentelements 100 used in this embodiment are guided out beyond the distalend 22 of the collecting basket 20. They are brought together at adistance from the distal end of the collecting basket 20 and areprovided with an atraumatic ball 101. The portion of the adjustmentelements 100 formed between the distal end of the second collectingbasket 20 and the atraumatic ball 101 likewise serves as a collectingbasket and is therefore designated by reference number 102. Thecollecting basket 102 is of open design, without any covering. Theadjustment elements are guided through eyelets 103 at the distal end ofthe second collecting basket 20. At the proximal end of the collectingbasket 20, the latter is secured in the catheter 40. Further coveringcan be provided by the channel element 50, as is set out in thepreceding embodiments.

The collecting basket 20 can again be composed of a metal mesh ortextile mesh, in which case the adjustment elements 100 and also thecollecting basket 20 are made of an elastic self-expanding material.Here, for example, a metal wire can be used, in particular nitinol asshape-memory material.

By provision of the eyelets 103, the adjustment elements can beshortened relative to the collecting basket 20 in order to draw acaptured object, in particular embolism material, into the collectingbasket 20. By pushing the channel element 50 forward, the closedcollecting basket 20 and the open collecting basket 102 are radiallycompressed and thereafter completely covered by the channel element.Conversely, upon withdrawal of the catheter, both collecting basketsexpand, because of their marked elasticity and shape, to their maximumdiameter of deployment. This corresponds to the embodiments ofcollecting baskets shown in the preceding figures. To capture embolismmaterial, or generally an object, it is not absolutely necessary to drawthe open collecting basket 102 into the closed collecting basket 20.Instead, the closed collecting basket 20 can be lengthened or pushedforward in relation to the open collecting basket 102 so that the objectcaptured in the open collecting basket again ends up in the closedcollecting basket 20.

It is possible to provide a relatively small number of adjustmentelements 100, in particular just three or four, these serving as guidewires for the advance movement of the collecting basket 20 in thedeployed state. Moreover, a small number of adjustment elements meansthat the capture of an object is not impeded.

The front view in FIG. 22 shows that all three adjustment elements arearranged at a uniform distance from one another, namely at an angle ofapproximately 120°, on the circumferential surface of the collectingbasket 20. However, a non-uniform distribution across this circumferenceis also possible.

FIGS. 23 and 24 show the relative adjustment of the open collectingbasket 102 with respect to the closed collecting basket 20. This viewalso shows the catheter 40 inside the channel element 50, with whichcatheter the collecting basket 20 is securely connected at its proximalend. Instead of eyelets 103, other guide elements can also be used.These serve in particular to stabilize the coaxial movement of thecollecting basket 102 relative to the collecting basket 20, and viceversa. By this means, a purely axial movement is allowed, whereas aradial movement or a movement tangential to the circumference is largelyavoided.

The distance s by which the adjustment elements 100 are drawn out at theproximal end of the catheter corresponds substantially to the distanceby which the open collecting basket 102 is drawn into the closedcollecting basket 20 and by which the open collecting basket thusshortens.

FIG. 25 shows a sequence of the procedure of capturing an object 2 usingthe embodiment of an extraction device according to the invention shownin FIGS. 21 through 24. Here, the channel element 50 with an innermandrel is first introduced over a guide wire into, for example, apulmonary artery circulation. After removal of the inner mandrel and, ifappropriate, of the guide wire, the open collecting basket 102 is firstpushed out of the channel element until the atraumatic ball 101 emergesfrom the distal end of the channel element (see FIG. 25 a)). After thechannel element has been drawn back, the open collecting basket 102 isreleased. The adjustment elements 100 expand and can be positionedaround the object to be captured, as is represented in FIG. 25 b).During the capturing procedure, the whole extraction device can berotated and the capturing thus made easier. Upon further withdrawal ofthe channel element 50, the collecting basket 20 is also released, as isshown in FIG. 25 c). The open collecting basket 102 is then drawn backinto the closed collecting basket 20 and, in so doing, is shortened, thecaptured object being drawn into the collecting basket 20, as is shownin FIG. 25 d). In the fifth step shown in FIG. 25 (see FIG. 25 e)), thechannel element is pushed distally in relation to the collecting basket20 and, in this way, both collecting baskets are drawn completely intothe catheter and compressed therein. During this procedure, the liquidportion of the captured object, in particular of a clot or embolus, canbe pressed through the meshes of the covering of the closed collectingbasket 20. The cell and tissue matrix of the clot or embolus then remainin the inside of the collecting basket. This matrix can be extractedoutside the patient's body by drawing back only the catheter or channelelement. After cleaning the two collecting baskets and reintroducingboth of them over the channel element still lying in the pulmonaryartery, the procedure can be repeated until the pulmonary artery isrecanalized.

In an alternative embodiment, it is also possible for the adjustmentelements 100 to run inside the circumferential surface 29 of thecollecting basket 20. This means it is possible to use a particularlylarge collecting basket 20 which can bear completely against an insidewall of a vessel without externally routed adjustment elements 100 oreyelets damaging this. An interlacing of the adjustment elements withthe circumferential surface 29 is also possible.

In a further embodiment, which is shown in FIG. 26, instead of threeadjustment elements 100, only one adjustment element 104 is provided.The latter is again routed through an eyelet 103, but lies on the insideof the collecting basket 20. The adjustment element 104 is also axiallydisplaceable and assumes the function of a guide wire. The adjustmentelement is curved at its distal end 105 in order to be able to take holdof objects to be captured. For this purpose, the distal end 105 can alsobe spoon-shaped, for example, to make this holding easier.

The adjustment elements, and in particular also the one adjustmentelement 104, continue along the circumferential surface of thecollecting basket 20 in the axis of the catheter or channel element, atthe same time permitting a relative axial movement.

FIG. 28 shows a further embodiment of a collecting basket 110 accordingto the invention. In contrast, for example, to the collecting basketsshown in FIGS. 17 and 18, the collecting basket 110 has a coating 111.This is provided in the interstices 112 of the mesh-like structure 113of the collecting basket. It is applied, for example, by immersion ofthe mesh-like structure of the collecting basket. This coating isdesigned as a membrane-like structure of the collecting basket or as afilm within the mesh-like structure of the collecting basket. Themembrane-like structure is suitably obtained using film-formingmaterials such as, for example, a natural or synthetic polymer formedfrom one or more monomers, in particular formed by polyaddition,polymerization or polycondensation, in particular a polycarbonate,polyester, polyamide, polyolefin or polyurethane. Polystyrenes too aresuitable for the coating. Depending on the application, a material canbe chosen having a greater or lesser flexibility or surface tension. Itshould in any event be so flexible that a capturing procedure is notimpeded by the coating but instead even improved by the latter. Theprovision of such a coating is expedient in particular for the captureof very small objects or object parts so that, when recovered, they arenot lost from the collecting basket. A coating can be provided in eachone of the above-described embodiments of collecting baskets.

All the above-described embodiments of collecting baskets can have acoating of the individual elements of their structure, in particular ofthe wires from which they are formed. Such a coating can suitably be abioactive surface coating, a coating with heparin, a carbonization ofnitinol when nitinol is used as shape-memory material for forming the atleast one collecting basket, nanotechnological or biotechnologicalcoatings, the application of radiopaque particles, in particulartantalum particles, a coating releasing an active substance, e.g. acoating with polymers, in particular polyurethane, which is/areimpregnated with active substances, e.g. medicaments. Such provision ofmedicaments and other active substances proves especially advantageouswhen the extraction device is used as a vena cava filter. The polymerscan also be microporous. By means of such a coating of the wires orelements of the structure of the collecting basket, it is possible toavoid the formation of (new) clots and also the adherence of endothelialcells. The material chosen for the coating is preferably one that doesnot cause inflammation in the patient's body and does not lead toformation of clots (=magic hat coating).

If the captured clot or captured material is too large to be able to bedrawn into a catheter, a means 120 is advantageously provided forcutting up the clot in the area of the collecting basket (see FIG. 29).Such a means 120 can, for example, be a wire 122 which is provided witha ball 121 or similar means and which is arranged inside the collectingbasket, in particular the collecting basket according to FIG. 28 closedfrom outside by provision of the coating, and can be drawn back into thelatter and in so doing cut up the clot or captured object. Instead of awire provided with a ball, any other desired means of cutting up theclot or captured object can be provided, for example an additional wirenoose 123, a coiled portion 124, a noose-shaped portion 125, acombination of different thicknesses or the like. Four differentembodiment variants are shown in FIG. 30.

For introduction of the collecting basket comprising a wire providedwith a material thickening, a guide wire is first pushed through acatheter to the site in the patient's body from where the object, inparticular the clot, is to be removed. A channel element is thereafteradvanced over the guide wire, and the guide wire is then removed. Thematerial thickening, in particular in the form of a ball, is advanced ona newly introduced wire or corresponding element via the channel elementas far as the object and cuts the latter up. If the distal portion of awire or similar element is provided with a coiled or noose-shapedportion, this wire or this element can itself be used as guide wire.This dispenses with the need for preliminary insertion of a guide wire.

Instead of using a wire, it is likewise possible to use a ballooncatheter together with a stent or similar expandable tubular element.Such an embodiment is particularly suitable for use in the case ofarteriosclerosis, for example, for removing, as foreign body, thecalcium material deposited on the vessel wall. For example, the ballooncatheter together with the collecting basket according to FIG. 28 isintroduced into the patient's vessel, for example the carotid artery,the collecting basket is opened, and the foreign body captured andremoved. The balloon catheter permits widening of the vessel and thusrelease of foreign bodies adhering to the wall.

To make it easier to transport the captured and cut up clot fragmentsand objects back out, a means 130 can advantageously be provided forsuctioning the clot fragments or object parts and objects. Such asuction means comprises, for example, a cannula 131 which ends in thearea of the collecting basket and via which the clot fragments or objectparts and objects can be sucked out. For this purpose, a partial vacuumis generated at the other end of the cannula, for example via a plunger132 in a cylinder part 133. The cannula can advantageously be brought bya catheter to the site in the body of the human or animal from where theclot or object is to be removed. Such a suction means can beadvantageously used both in the embodiments with normal mesh-likestructure and also in the coated embodiment according to FIG. 28, as isshown in FIG. 29, and above all also where a means is provided forcutting up or separating the object or object parts. Toward the proximalend, the cannula 131 has a branch piece 134 comprising the cylinder part133 with plunger 132 and a grip part 135 for holding when actuating thewire 122. The arrows in FIG. 29 indicate the direction of withdrawal andthe direction in which a partial vacuum is generated for sucking objectsout.

In addition to the embodiments mentioned and described above, a greatmany others are possible, in particular also combinations of thedescribed forms in which, where first and second compressible andexpandable collecting baskets are provided between which objects can becaptured, the collecting baskets being able to be drawn one into theother, at least one collecting basket has an umbrella-like design in theexpanded state. With provision of at least one compressible andexpandable collecting basket having a distal end and a proximal end, atleast one adjustment element can be secured at the distal and/orproximal end in such a way that the at least one collecting basket canbe controlled by the latter and changed in shape. In addition, oralternatively to this, a coating of the collecting basket is alsopossible. In particular, it is also possible to use combinations ofsectioned tubes and braided fabrics, scrims or woven fabrics withsuitable choice of material for the collecting basket or baskets.

LIST OF REFERENCE LABELS

-   1 extraction device-   2 object-   3 cavity-   4 inside wall of vessel-   10 first collecting basket-   11 adjustment element-   12 distal end-   13 proximal end-   14 guide cannula-   15 adjustment element part-   16 adjustment element part-   17 filament-   18 point of attachment-   19 point of emergence-   20 second collecting basket-   21 adjustment element-   22 distal end-   23 proximal end-   24 sleeve element-   25 tubular element-   26 first filament-   27 second filament-   28 opening-   29 circumferential surface-   30 guide wire-   40 catheter-   41 proximal end-   50 channel element-   60 reducing element-   61 reducing element-   70 lengthening piece-   71 opening-   72 proximal end-   73 opening-   74 guide cannula-   75 hook-shaped element-   80 arrow-   90 slotted tube-   91 cut-   100 adjustment element-   101 atraumatic ball-   102 collecting basket-   103 eyelets-   104 adjustment element-   105 distal end-   110 collecting basket-   111 coating-   112 interstice-   113 mesh-like structure-   120 means for cutting-   121 ball-   122 wire-   123 wire noose-   124 helical portion-   125 noose-shaped portion-   130 suction means-   131 cannula-   132 plunger-   133 cylinder part-   134 branch piece-   135 grip part-   x distal area-   y proximal partial area-   a₁ distance-   d₁ vessel diameter-   d₂ widened vessel diameter-   s stretch

1. An extraction device for extracting objects, in particular clots, foreign bodies, etc., from cavities in a human or animal body, with first and second compressible and expandable collecting baskets between which the object can be captured, said collecting baskets being mutually displaceable and being able to be drawn one into the other, wherein at least one collecting basket is umbrella-like in the expanded state and is designed with flexible wire-like adjustment elements for deliberately changing the shape and/or position of the collecting basket so that the object can be captured in the latter and can be drawn into the other collecting basket.
 2. The extraction device as claimed in claim 1, wherein the umbrella-like collecting basket opens in the direction toward the other collecting basket or in the direction away from the other collecting basket.
 3. The extraction device as claimed in claim 1, wherein both collecting baskets are provided with at least one adjustment element for deliberately adjusting the shape and/or position of the collecting baskets.
 4. An extraction device for extracting objects, in particular clots, foreign bodies, etc., from cavities in a human or animal body, with at least one compressible and expandable collecting basket having a distal end and a proximal end, wherein at least one wire-like flexible adjustment element is secured at the distal and/or proximal end in such a way that the at least one collecting basket can be deliberately oriented by the latter and changed in shape.
 5. The extraction device (o as claimed in claim 4, wherein the at least one adjustment element has one or more thin wires.
 6. The extraction device as claimed in claim 4, wherein the at least one adjustment element is arranged on the outside and/or inside of the at least one collecting basket, in particular at least partially integrated into the circumferential surface of the collecting basket and/or laced into this.
 7. The extraction device as claimed in claim 4, wherein the at least one adjustment element protrudes beyond the outstretched length of the at least one collecting basket and is arranged to be actuated in particular from the proximal end, in particular to be actuated via a handgrip.
 8. The extraction device as claimed in claim 4, wherein, with an adjustment element provided at the proximal end of the collecting basket, the latter has an asymmetrical design, in particular lengthened on one side in the area of attachment of the adjustment element, and/or is provided with a hook-shaped element for engagement of an adjustment and/or guide element.
 9. The extraction device as claimed in claim 4, wherein the adjustment element or elements are secured on the collecting basket in a branched-out configuration and are brought together in groups proximally.
 10. The extraction device as claimed in claim 4, wherein the at least one adjustment element is in one piece with the collecting basket.
 11. The extraction device as claimed in claim 4, wherein the distance between the distal end of the collecting basket and at least one proximal point of attachment or point of emergence of the at least one adjustment element is constant for different designs of the collecting basket.
 12. The extraction device as claimed in claim 4, wherein the proximal end of the at least one collecting basket can be fixed or is fixed in a tubular element, in particular a catheter, and the adjustment element or elements are guided or can be guided through the tubular element.
 13. The extraction device as claimed in claim 4, wherein the at least one collecting basket is designed so that it shortens in its longitudinal direction upon widening and lengthens when its cross section is reduced, and in particular can be expanded to a diameterd, greater than the diameter of the cavity to be cleared, for partial widening of the cavity.
 14. The extraction device as claimed in claim 12, wherein a sleeve element for strengthening the connection between tubular element and collecting basket is provided at the proximal end of the at least one collecting basket.
 15. The extraction device as claimed in claim 12, wherein the tubular element is made in one piece with the second collecting basket and is provided at least partially with a cut permitting expansion and compression.
 16. The extraction device as claimed in claim 11, wherein reducing elements arranged transversely with respect to the longitudinal extent of the at least one collecting basket are provided, in particular in the area of the proximal and/or distal ends of the collecting basket and/or in the area of the at least one proximal point of attachment or point of emergence of the at least one adjustment element, and the reducing elements are in particular nooses.
 17. The extraction device as claimed in claim 4, wherein the adjustment element or elements are fixed or movably guided in at least one tubular element, in particular a catheter.
 18. The extraction device as claimed in claim 1, wherein a guide cannula is provided which is secured on the distal end of the first collecting basket.
 19. The extraction device as claimed in claim 18, wherein the guide cannula and/or the tubular element or elements is/are made of a flexible material, in particular a metal, a metal alloy, a plastic or another flexible material or a combination of materials, in particular of nitinol.
 20. The extraction device as claimed in claim 4, wherein a channel element is provided which has an internal diameter such that the at least one collecting basket, a guide cannula and/or tubular elements and the adjustment element or elements can be guided through it.
 21. The extraction device as claimed in claim 20, wherein the channel element is made of a stable and at least partially flexible material, in particular of a plastic, metal, a metal alloy, in particular nitinol, in particular a thin-walled nitinol tube.
 22. The extraction device as claimed in claim 4, wherein at least one collecting basket is made of a braided fabric and/or woven fabric and/or scrim, in particular a wire braid and/or woven wire fabric and/or wire scrim and/or at least one collecting basket is composed of a tube slotted along at least part of its length and/or is provided with a coating.
 23. The extraction device as claimed in claim 4, wherein the at least one adjustment element is formed from a part of a braided fabric, woven fabric, scrim, or a slotted tube.
 24. The extraction device as claimed in claim 22, wherein the cuts in the slotted tube are made in such a way as to afford the maximum ratio of shortening and widening upon expansion of the collecting basket.
 25. The extraction device as claimed in claim 24, wherein the cut or cuts in the slotted tube are made long in comparison to the lengthwise extent of the collecting basket.
 26. The extraction device as claimed in claim 4, wherein the at least one collecting basket is made of a biocompatible material, in particular a metal or a metal alloy, in particular a stainless steel or nitinol and/or the material of the at least one collecting basket is coated with a material, in particular a biocompatible surface coating, heparin, a carbonization of nitinol, a nanotechnological coating, radiopaque particles, a coating releasing active substance, an in particular microporous biotechnological or other coating.
 27. The extraction device as claimed in claim 4, wherein partial areas of the at least one collecting basket are made of material of different diameter, in particular an expandable partial area (x) of the at least one collecting basket is made of a material with a thinner cross section or has a braided fabric or scrim or woven fabric with filaments of different diameter.
 28. The extraction device as claimed in claim 27, wherein the material of the at least one collecting basket in at least one partial area is chemically and/or mechanically treated, in particular etched, electrolytically polished, microground or otherwise treated.
 29. The extraction device as claimed in claim 4, wherein a guide wire and/or inner mandrel is provided along which the at least one collecting basket can be displaced and/or can be inserted into the cavity.
 30. The extraction device as claimed in claim 1, wherein at least the second collecting basket has a self-opening partial area (x) and a self-closing partial area (y), which self-closing partial area (y) can be opened deliberately by at least one adjustment element.
 31. The extraction device as claimed in claim 4, wherein the extraction device can be used in conjunction with an endoscope with or without provision of a channel element.
 32. The extraction device as claimed in claim 4, wherein a means is provided for cutting or separating objects, in particular a wire provided with a material thickening, in particular a ball, a helical portion, a noose-shaped portion, a combination of these or some other type of material thickening, which wire can be or is arranged so as to be movable inside the collecting basket, and/or a balloon catheter provided with a stent or such like element.
 33. The extraction device as claimed in claim 4, wherein a suction means is provided for suctioning of objects or parts of objects, in particular a cannula or such like tubular means which can be guided into the area of the collecting basket and can be acted on by a partial vacuum. 